This application claims the priority benefit of Japanese patent application No. 2000-329414, filed on Oct. 27, 2000, and entitled xe2x80x9cDisk Drive Apparatus, Hard Disk Drive, and Enclosure for Hard Disk Drive.xe2x80x9d
1. Technical Field
The present invention relates in general to a disk drive apparatus represented by a hard disk drive.
2. Description of the Related Art
A hard disk drive (hereinafter abbreviated as an HDD) most popularly used as data storage means for a computer has a construction such that a single or a plurality of magnetic disks are disposed coaxially and are driven by a spindle motor. Data is read from and written on the magnetic disk with a magnetic head provided so as to be opposed to the magnetic disk. The magnetic head is driven by an actuator, generally by a voice coil motor (hereinafter abbreviated as a VCM). The magnetic disks, magnetic head, and actuator are contained in an enclosure called a disk enclosure. The disk enclosure is made up of a thin box-shaped base made of, for example, an aluminum alloy and a top cover for sealing an opening of the base.
One of the major technical problems with the HDD is to increase the speed of reading data stored on the magnetic disk and the speed of writing data on the magnetic disk. One means for solving this problem is to increase the rotational speed of the magnetic disk. However, the increase in rotational speed of the magnetic disk increases the velocity of an air flow generated by the rotation of the magnetic disk. As a result, a flutter of the magnetic disk increases. If a flutter of the magnetic disk (hereinafter referred to as a disk flutter) occurs, a relative positional relationship between the magnetic disk and the magnetic head changes, so that the increase in disk flutter has an adverse influence on the accuracy in reading and writing data. Specifically, it is assumed that when data is written, the data is written undesirably on a track that is different from the track on which the data is supposed to be written, or when data is read, the data is read undesirably from a track that is different from the track from which the data is supposed to be read. In particular, if the storage density is increased to increase the capacity of the magnetic disk, this tendency becomes great.
3. Problems to Be Solved by the Invention
Although the rotational speed of a 3.5-inch magnetic disk was 7200 rpm at first, a high rotational speed of 10,000 rpm has been adopted, and further a high-speed HDD rotating at a rotational speed exceeding 10,000 rpm has been developed. As the velocity of an air flow generated in the HDD increases, a flutter of the magnetic disk becomes remarkable. On the other hand, as the rotational speed of the magnetic disk increases, the velocity of the air flow generated in the HDD increases. Therefore, the increase in rotational speed of the HDD makes a problem of accuracy in reading and writing data caused by a flutter of the magnetic disk serious.
Accordingly, an object of the present invention is to provide a disk drive apparatus capable of restraining a flatter of a magnetic disk in a high-speed HDD.
The inventor presumed that the disk flutter is not affected simply by the rotational speed of magnetic disk only, but a turbulent flow generated by the interruption of an air flow taking place on a magnetic disk when the magnetic head is positioned over the magnetic disk also has an influence. Based on this presumption, the inventor took measures for making the air flow in the HDD more stable, specifically, provided a new air flow path in the HDD, by which a knowledge that the disk flutter could be reduced was obtained. The disk drive apparatus in accordance with the present invention has been invented based on this knowledge.
Therefore, the present invention provides a disk drive apparatus comprising: a disk-like medium rotationally driven around a rotating shaft, the disk-like medium being used to store data; a reading/writing head for storing data and playing back the data; an actuator for causing the reading/writing head to seek on the disk-like medium; an enclosure for containing the disk-like medium, the reading/writing head, and the actuator, the enclosure having a side wall standing at the periphery thereof; and a bypass channel for supplying part of an air flow generated in the enclosure by the rotational drive of the disk-like medium from an exterior of the enclosure in the radial direction of the disk-like medium toward the disk-like medium.
The disk drive apparatus in accordance with the present invention can reduce a disk flutter by supplying part of the air flow generated in the enclosure by the rotational drive of the disk-like medium to the disk-like medium through the bypass channel.
In the disk drive apparatus in accordance with the present invention, it is preferable that the bypass channel comprise an inflow port through which an air flow enters, a channel for guiding the air flow entering through the inflow port, and an outflow port through which the air flow introduced into the channel is discharged, and the outflow port be provided in the vicinity of the range of seek of the reading/writing head performed by the actuator. The disk flutter is produced by the rotational drive of the disk-like medium. When the reading/writing head is positioned over the disk-like medium, a turbulent flow is generated by the presence of the reading/writing head, so that the disk flutter is increased. Therefore, it is understood that by supplying an air flow in a straightened state from the bypass channel to the vicinity of the range in which the reading/writing head moves, that is, the seek range, an effect of reducing the turbulent flow is produced, and thereby the disk flutter can be reduced.
Also, in the disk drive apparatus in accordance with the present invention, the inflow port and the channel can be formed along the side wall. In other words, the side wall of the enclosure is utilized to form the bypass channel.
Further, in the disk drive apparatus in accordance with the present invention, the configuration can be such that the disk drive apparatus has a discharge port for discharging part of the air flow generated by the rotational drive of the disk-like medium to the outside in the radial direction of the disk-like medium, and part of the air flow discharged through the discharge port goes to the inflow port. The purpose of this is to effectively keep the air flow supplied from the bypass channel toward the disk-like medium. The hard disk drive is provided with a filter mechanism on the exterior of the drive, and this filter mechanism can form the discharge port.
Also, the present invention provides a disk drive apparatus comprising: a disk-like medium rotationally driven around a rotating shaft, the disk-like medium being used to store data; a reading/writing head for storing data and playing back the data; an actuator for causing the reading/writing head to seek on the disk-like medium; and an enclosure for containing the disk-like medium, the reading/writing head, and the actuator, characterized in that the enclosure has a side wall standing at the periphery thereof, a disk container room for containing the disk-like medium, and a wall standing along the side wall so as to be separated with a predetermined space from the side wall, one end of the wall facing the disk container room.
In this disk drive apparatus, the enclosure has a side wall standing at the periphery thereof, a disk container room for containing the disk-like medium, and a wall standing along the side wall so as to be separated with a predetermined space from the side wall, one end of the wall facing the disk container room, and the space between the side wall and the wall one end of which faces the disk container room forms the aforementioned bypass channel. Therefore, by supplying part of the air flow generated by the rotational drive of the disk-like medium from the space toward the disk-like medium, the disk flutter can be reduced.
The present invention can be applied to a hard disk drive serving as a disk drive apparatus. Specifically, the hard disk drive in accordance with the present invention comprises: a disk assembly having a magnetic disk for storing data and a spindle motor for driving the magnetic disk rotationally; a magnetic head for storing data and playing back the data on and from the magnetic disk; an actuator for causing the magnetic head to seek on the magnetic disk; a base having a disk container room for containing the disk assembly and an actuator container room for containing the actuator, the base having a side wall standing at the periphery thereof; and an air flow path having an inflow port opening to the actuator container room, an outflow port opening to the disk container room, and a channel connecting the inflow port to the outflow port.
The hard disk drive in accordance with the present invention has the air flow path having the inflow port opening to the actuator container room, the outflow port opening to the disk container room, and the channel connecting the inflow port to the outflow port. Therefore, part of the air flow generated in the actuator container room by the rotational drive of the magnetic disk can be supplied toward the magnetic disk through the air flow path. Therefore, the turbulent flow generated by the presence of the magnetic head over the magnetic disk is stabilized, and thereby the disk flutter is reduced.
Also, in the hard disk drive in accordance with the present invention, in order to sufficiently perform a function of stabilizing the air flow, it may be desirable that the outflow port be open to the downstream side along the direction of rotation of the magnetic disk with respect to the seek range of the magnetic head.
In this hard disk drive, the filter mechanism can be provided on the outside in the radial direction of the magnetic disk on the further downstream side of the outflow port. It is judged to be effective in stabilizing the air flow that a flow is produced such that as described above, the air flow discharged to the filter mechanism enters the air flow path, and is supplied toward the magnetic disk.
Still further, in the hard disk drive in accordance with the present invention, a flow path forming wall can be provided ranging from the filter mechanism to the air flow path so as to be separated with a predetermined space from the side wall. This is an effective means for causing the air flow discharged to the filter mechanism to enter the air flow path surely.
Also, the present invention provides a hard disk drive comprising: a magnetic disk for storing data; a magnetic head for storing data and playing back the data on and from the magnetic disk; an actuator for supporting the magnetic head and for loading or unloading the magnetic head onto or from the magnetic disk; a base having a container room for containing the magnetic disk, the magnetic head, and the actuator and a side wall standing at the periphery of the container room; and a ramp disposed in the container room of the base so as to be separated with a predetermined space from the side wall to support the actuator at the unload time of the magnetic head.
In the above-described hard disk drive in accordance with the present invention, the ramp is disposed so as to be separated with a predetermined space from the side wall of the base, and this predetermined space forms the aforementioned bypass channel. Therefore, part of the air flow generated in the container room by the rotational drive of the magnetic disk can be supplied toward the magnetic disk through the space between the ramp and the side wall. As a result, the turbulent flow generated by the presence of the magnetic head over the magnetic disk is stabilized, and thereby the disk flutter is reduced.
In the hard disk drive in accordance with the present invention, the base can be provided with a space of a predetermined width along the side wall in a portion where the actuator is contained. The purpose of this is to keep a flow path of the air flow.
Also, in the hard disk drive in accordance with the present invention, the size of the magnetic disk is preferably smaller than the size of a magnetic disk corresponding to the form factor of the base. This is because an adequate room is necessary to provide the space between the ramp and the side wall of the base. The form factor means a factor relating to a form such as a shape and a size. At present, three form factors of 5.25 inches, 3.5 inches, and 2.5 inches are available. The standard widths excluding a tolerance are 5.75 inches (146.05 mm), 4.0 inches (101.6 mm), and 2.75 inches (68.95 mm). The form factor of 3.5 inches does not mean that the diameter of the magnetic disk mounted in the HDD is 3.5 inches. Generally, a hard disk drive with a form factor of 3.5 inches has been mounted with a magnetic disk of 95 mm (3.74 inches). However, if the 95-mm magnetic disk corresponding to the form factor of 3.5 inches is mounted, it is difficult to provide a space between the ramp and the side wall of the base. Although the space can be provided, the side wall must be made thin in this case, resulting in a decrease in stiffness of the base.
Thereupon, for the high-speed hard disk drive, it is preferable that the size of the magnetic disk be smaller than the size of a magnetic disk corresponding to the form factor of the base. The reason for this is that the decrease in diameter of the magnetic disk can restrain an increase in power consumption of the spindle motor for rotating the magnetic disk. Therefore, the present invention is suitable for a high-speed hard disk drive in which a disk flutter is liable to occur.
The above-described bypass channel or air flow path can be formed in an enclosure forming a hard disk drive. Therefore, the present invention provides such an enclosure. Specifically, the present invention provides an enclosure for a hard disk drive, comprising: a side wall standing at the periphery of the enclosure; a disk container room for containing a magnetic disk for storing data; and a wall standing along the side wall so as to be separated with a predetermined space from the side wall, one end of the wall facing the disk container room.
Also, the present invention provides an enclosure for a hard disk drive, used for a hard disk drive of a load/unload type, comprising: a container room for containing a magnetic disk for storing data magnetically and an actuator for driving a magnetic head, the magnetic head being used to store data and play back the data on and from the magnetic disk; a side wall surrounding the container room; and a ramp disposed in the container room so as to be separated with a predetermined space from the side wall to hold the magnetic head at the unload time of the magnetic head.